1. Field of the Invention
The invention relates to a process for correcting the richness of an air-fuel mixture admitted into an internal combustion engine with electronic injection of the pressure-speed type, to keep the richness constant as a function of the air temperature entering the cylinders and regardless of the speed and pressure in the intake manifold.
2. Discussion of the Background
For an injection engine of the pressure-speed type which comprises a computer for controlling the opening of the injectors, but lacking a probe for measuring the richness of the exhaust gases making it possible to control the richness of the mixture at the intake to the latter, difficulties appear during adjusting of the correction of richness as a function of the air temperature. In particular, a change in the richness during extended idle speeds is found.
A study of the influence of certain parameters such as the water temperature of the engine, the pressure in the intake manifold or the engine speed, on the heating of air at the intake between the place where its temperature is measured by a probe placed upstream from the throttle butterfly and the valves have made it possible to obtain a law of heating the air that eliminates said drawbacks.